Metal pipes are subjected to corrosion, particularly when they are laid in the ground or under water. It has been described in the art that such pipes can be protected from this corrosion by a protective coating of asphalt coated in turn with concrete. Such a coating not only renders the pipes heavy and is difficult to be put on the pipe joints, but the coating is not sufficiently flexible so that cracking may occur during the pipe laying.
An improved technique known in the art provides for a protective coating for pipes that comprises asphalt, sand, limestone dust and asbestos or glass fiber fillers. Whereas such a coating is reported to be more flexible than a concrete coating, it would be desirable to have a coating material available with still further improved crack resistance.